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FAQs | Global Energy Transition Masterclass

CO2

Ammonia

Direct Air Capture

Hydrogen

LNG - Tank Gauging

Biofermenter

LNG - Tank Gauging

QUESTION: LNG storage tanks are almost never put into service. What are the advantages of Servo level technology in this condition or application? We operate an LNG terminal and what do you recommend for level measurement in LNG tanks and how do you maintain the reliability of the gauge?

This is a very important question. LNG storage tanks are typically operated for 20 years or more without being commissioned. So imagine the importance of using the right level technology to ensure reliability and availability of data for safe tank operation.

The advantages of servo technology from Endress+Hauser Servo

With Servo, you can isolate the gauge even when the tank is in operation. When the gauge needs maintenance, you can lift the displacer into the measurement chamber and then close the isolation valve. Once it is closed, you can perform a check, or in some other countries that require an annual check of the entire gauge, you can do this.
The lower and upper reference points can be checked to determine if the meter is functioning properly. This can be done at any time without interrupting operation.

QUESTION: What about the vapor effect - is it a problem?

This is another unique advantage of Servo technology. BOG is inevitable, also depending on how long the LNG is stored in the tank. You have methane with a boiling point of -160 ^oC, and nitrogen with a boiling point of -196 ^oC. So the meter has to deal with those vapors in the tank, so technologies like radar can be affected by vapors that can cause echo loss. For Servo, because it is a direct contact measurement, it is not affected by vapor phase.

QUESTION: Is there anything to consider when measuring temperature in LNG? So far, we have installed these thermometers like any other.

In LNG applications, there can be a temperature difference of 200 Kelvin with the environment.

If this is not taken into account, there will be energy transfer into the line, which will affect the reading of the temperature measurement. You will see a value that is higher than reality.

Of course, efficient external insulation helps, but there are also technical aspects, such as installing nozzles under the pipe and increasing the wetted insertion length by installing it in a pipe bend.

QUESTION: What safety aspects have to be considered when storing LNG? What do you offer as a complete solution.

The most discussed topic is stratification, which can lead to flashover, as well as leak detection and product overfilling.

So for the safe operation of the LNG tank. We have our LMS software (LNG management software) that allows stratification detection, flashover prediction, temperature monitoring software for cooling and leak detection.

In tank instrumentation, we have a complete range for Servo as primary and secondary gauge, or if different technologies are required, we can provide radar, independent level alarm, LTD gauge, multi-point temperature and also skin-point temperature for cooling and leak detection.

It is a solution with numerous components. To get more details, please get in touch with us.

QUESTION: Do you have a solution for bunkering LNG?

The IMO (International Maritime Organization) has set ambitious targets for greenhouse gas (GHG) emissions. The shipping industry is beginning to use LNG as a fuel, and pilot projects are underway to use ammonia, methanol and hydrogen. All of these projects are in various stages of development.

LNG as a fuel is gaining momentum, and we have developed a solution for bunkering LNG that combines reliable volume measurement with a Coriolis mass flow meter, inline composition measurement with a Raman analyzer, and a bunker computer for calculations and reporting. This also includes the calculation of the methane number.

Hydrogen

QUESTION: Is there anything to consider when measuring the temperature in an electrolysis application?

For hydrogen applications, we recommend using austenitic steel thermowells with a higher nickel content.

For high temperature applications, you have to consider H₂ diffusion through the steel.

In this case, we would use an adapted thermometer connection head to prevent H₂ from "creeping" further into the measuring insert.

QUESTION: What are the most important points to consider when choosing the right flow meter for H₂?

QUESTION: Are there material combinations to consider for H₂ in flow applications?

We follow ASME standard B31.12, as should any supplier.

QUESTION: What experience do we have in measuring H₂ flow rates - can you name some applications?

H₂ is traditionally a feedstock for the chemical and petrochemical industries, and we have been supplying the refining, ammonia and petrochemical industries for years.

H₂ is used in these applications at low pressure (about 67 bar), for example in amine absorption, a gas treatment process very well known in the natural gas industry to remove CO₂ and H₂.

QUESTION: Hydrogen is used in refineries for hydrogenation processes such as hydrocracking and hydrotreating. I assume we are working with lower hydrogen pressures there. How different is it in the new applications?

In any case, the H₂ gas is used to improve the hydrogen-carbon ratio in the cracked molecules to obtain a wider range of products such as gasoline or kerosene. This application takes place under low pressure conditions.

As the world is looking for cleaner alternatives to reduce CO₂ emissions, H₂represents the best alternative to replace fossil fuels in the long term. Therefore, H₂ is treated not only as a raw material, but as a main energy source, and we therefore see the demand for larger dimensions for the transportation of H₂ and applications with higher pressure, for example, for H₂ transport economy.

QUESTION: Is it the same for alkaline electrolyzers and PEM electrolyzers?

In terms of process conditions, the two are completely different, as the process conditions for PEM electrolyzers are more demanding, the pressure requirements are higher (up to 80 barg) and the temperatures reach up to 100 ^oC. In contrast, the process conditions for alkaline electrolyzers are up to 3 barg higher (there are major differences here), and alkaline electrolyzers have been used in industry for many years.

The efficiency of PEM electrolyzers is also higher than that of alkaline electrolyzers.

QUESTION: Which flowmeter do you recommend for the hydrogen application in electrolyzers?

As mentioned above, we have been supplying our Coriolis meters in the refinery (amine absorption) for many years, and the electrolyzer is also a low pressure application (<100 barg) that matches the performance and design of our Coriolis meters accordingly.

QUESTION: Hydrogen is the smallest molecule. Can it penetrate the diaphragm during pressure measurement?

Our standard pressure transmitters are 316L stainless steel diaphragms with a thickness of e.g. 50 My. Under certain process conditions - typically it depends on pressure and temperature, but also on the media if it is not pure hydrogen - it can diffuse through these membranes. Under these conditions, atomic hydrogen is produced. Diffusion through the membrane causes hydrogen to gradually accumulate in the pressure transfer fluid (filling oil) located behind the membrane. Subsequently, changes in pressure or temperature can cause the saturation limit of hydrogen in the filling oil to be exceeded, resulting in hydrogen bubbles forming in the oil. This can lead to a short-term zero point shift and, in the case of increased diffusion, even to a malfunction. How can this now be avoided: If you coat the membrane with gold, this will completely prevent diffusion of hydrogen into the interior of the membrane.

Follow-up question: What about other wetted parts?

In this case, the issue is not diffusion, but brittleness. A change in brittleness caused by the penetration and intercalation of atomic hydrogen into the metal lattice.

The most important behavior of metals is that susceptibility to hydrogen embrittlement increases with increasing material strength (hardness). Austenitic materials with high nickel content between 10 and 30 percent are a good choice for hydrogen service. SuperDuplexDuplex or other commonly used materialsalloys such as C22C276 or Alloy 400 are not the best choice in this case, but rather the classic 316L material. Tantalum, for example, can become very brittle when operated with high-temperature oxygen or nitrogen or with hydrogen at any temperature.

QUESTION: Do you have a reference for level measurement in liquid hydrogen storage tanks?

Yes, we have used servo technology. We have installed our Servo gauges in two of the first large-scale storage tanks in Japan, one in onshore storage tank and another in LH2 vessel, which have been in operation for more than 1.5 to 2 years.

Follow-up question: Why did the customer choose Servo?

Servo is proven to be the best technology for cryogenic applications and LNG.

Another key issue that was part of the main discussion was the accuracy advantage of servo technology. The accuracy of servo technology at reference conditions is +/- 0.4 mm, for this application using a mathematical calculation with an estimated density of 0.708 g/cm3 hydrogen, the calculated accuracy is +/- 1.9 mm for a larger displacer of 120 mm and +/- 4.3 mm for an 80 mm displacer. For larger tanks, this difference in accuracy thus corresponds to an enormous amount of money.

QUESTION: In our refinery we have problems with controlling the ratio in SMR, is there any recommendation?

Steam methane reforming is a mature production process that uses high temperature steam to produce hydrogen from a methane source, such as natural gas. In steam methane reforming, methane reacts with steam in the presence of a catalyst to produce hydrogen, carbon monoxide, and a relatively small amount of carbon dioxide. Controlling the ratio is critical for efficient operation. This is made possible by an inline Ram Analyzer that measures the composition of methane, CO, H₂ and CO₂.

CO₂

QUESTION: Absorption based on amine solvents is a typical process unit in gas sweetening and CO₂ capture. What are the main process challenges and how can the process be optimized?

What are the key considerations for operating an amine absorption plant and what are the recommendations for optimizing the operation?

Amine solvent-based chemical absorption is the most mature technology for gas sweetening and carbon capture. Challenges of the process include amine losses, degradation, and energy efficiency during rich amine regeneration. These issues can lead to plant downtime and financial losses.

Inline monitoring of CO₂ capture solvent quality using Raman spectroscopy replaces tedious offline analysis, provides reliable prediction of total CO₂ concentration and amine concentration, and monitors variations in solvent quality and degradation, minimizing solvent losses and degradation.

QUESTION: When CO₂ is captured from exhaust gases, aggressive or corrosive gases (sour gas) can be produced as an intermediate product. Besides the conventional installation, are there new solutions to reduce the risk of leakage that could harm plant personnel and the environment?

Yes, for really dangerous applications we recommend the use of a double-sealed thermowell. If this is damaged by corrosion, for example, a second seal closes the containment, while in parallel a pressure switch triggers an alarm. The temperature measurement remains active for a time so that a controlled shutdown of the plant can be initiated.

QUESTION: Is your pressure portfolio suitable for cryogenic applications? What is the minimum temperature that the sensor cell can handle?

The specified process temperature of a pressure transmitter is usually -40 °C. This limitation comes mainly from the seals and electronics inside the device. However, with the Hampsonmeter principle, we can measure much lower temperatures. Impulse tubes from the insulation of the tank. In these impulse tubes, the temperature of the medium rises and it becomes a gas. What we see on the transmitter as temperature depends on the length of the impulse tubes or also called wet legs. If we design these tubes long enough, we can ensure that the temperature at the pressure diaphragm reaches a point that will not harm the device itself. As a rule of thumb, for every 30 cm of impulse tube, we have half the negative temperature. For example, we have some nitrogen tanks next to our production where we have exactly the same installation principle.

Ammonia

QUESTION: We experience significant errors when measuring ammonia with radar technology. How can this error be eliminated?

Ammonia is not so easy to measure. However, with our philosophy of different measurement technologies, we can deal with it. Theoretically, you can measure it with low-frequency radar, but there are some limitations, especially when ammonia starts to boil. You could avoid this overlay, but it's not that common. In such cases, we usually opt for GWR. With GWR, the electromagnetic wave moves along the rod and is therefore more focused. In such cases, we have a very reliable measurement. For larger tanks, we can also offer the servo measuring principle, which is a kind of electromechanical measuring principle with a displacer on a wire and measures with the highest accuracy. As you can see, every application has its own challenge. And our large portfolio offers the answer.

QUESTION: Why do certain radar frequencies have problems measuring the level in ammonia tanks?

Ammonia produces gases that are polar by nature. That is, they have a strong polarity. These polar gases absorb certain radar signal frequencies. Especially at higher frequencies like 26 GHz or 80 GHz. You can measure under these conditions with a guided wave radar, which emits a beam of many frequencies along a conducting rod or cable. And a gas phase compensation system built onto the rod also compensates for the velocity delay of the radar signal, so you can still measure accurately.

QUESTION: What are the most important points to consider when selecting the right flowmeter for H₂?

Besides the normal process conditions that need to be considered when selecting a flowmeter for any application, such as fluid properties, process or temperature conditions, for H₂ it is especially important to understand the density (as we know, the density of H₂ is even lighter than that of natural gas) and, of course, the pressure, which has a direct impact on the density of the medium.

QUESTION: We have problems with the flow measurement of wet gas in our plant. Do you have a corresponding product in your portfolio?

Wet gas is defined as natural gas or other gases with a small amount of liquid. The term "wet gas" has been used to describe a range of conditions from a wet gas to a high liquid content. Conventional flow measurement techniques have their pitfalls and tend to over or under measure depending on the LVF. Our G300 process ultrasonic flowmeter is designed with a unique transducer and signal processing design.

Unique features of the sensor design include a large gap between the transducer and housing, a special filter design, and liquid drains.

Biofermenter application

QUESTION: Which is better for foamy applications, such as desalinators or separators? Free space radar or guided shaft.

Guided Wave. Simply because one emits more energy per square inch/cm and simply shoots through the foam to the liquid level below. We supply most guided wave radars or even free space radars with a second 4...20 mA output for these applications, so you can measure not only the liquid level, but how strong the reflection is, so you know if there is foam and even how much.

QUESTION: So what is in these rods or cables of a guided wave radar?

Nothing. You can cut them to length in your application. However, if you shorten or lengthen them, please tell the instrument. Just like you changed the 0 point or "blank" point. You can press a button and let the unit do this itself while the tank is empty. Or you can tell the unit how much you cut off or welded on when the tank is already full. It's that simple.

Energy Monitoring

QUESTION: What is the easiest way to measure the steam consumption of a cost center or department?

We recommend energy calculators such as RS33 or RMS621. They use internationally recognized steam tables. No programming or additional input is required in the DCS.

Direct Air Capture

QUESTION: What is the projected cost (per ton of CO₂) for direct air capture? What is the tipping point for Direct Air Capture so that the technology can be deployed at scale?

We believe that once the urgency and need for carbon capture is fully understood and the right policy tools are in place, the global carbon price will settle in the $100 to $200 per ton range.

The key to achieving low costs is the speed of industrial implementation. To be an effective solution to the climate crisis, an entire carbon capture industry will need to develop over the next 10 to 20 years, creating multi-billion ton carbon capture capacity by 2050.

We project that the cost potential of our current direct air capture technology will be $250-300/ton for a one million ton capacity by 2030. Further industrialization within the ecosystem of this emerging industry will bring this cost down to $100-200/t.

The key elements for cost reduction are capacity expansion combined with technology and process optimization.

For further questions, please feel free to contact sales@climeworks.com.

QUESTION: What is the approximate price of such a CO₂ capture system ($/ton CO₂), CAPEX and OPEX.

Our exact capture cost is confidential, but around $600-800 per ton of CO₂ is a good guideline.

Costs depend on several factors and can vary from project to project. Providing a specific number on costs requires a stable operation. Our goal is to bring direct air capture capacity to market as soon as possible, which we have done with Orca.

If you have any further questions, please feel free to contact us at sales@climeworks.com.